Running 4 speakers from a 2-channel amp

Heat does shorten transistors life.Running two 8 ohm speakers is about the limits of most amps(4 ohms total).All the amps I've owned do parallel the speakers through the speaker switches.Some budget receivers run them in series,but that ruins the sound because both speakers would be using the others crossover along with its own.The 8+6 ohm speaker combo is over doing it in my opinion.The other peoples ideas sound better if you like the amp and want it keep on going.

Thank you all for the facts n ideas. It sure cut out a lot of time for me. I'm still thinking about my next move.

I am running 18 separate speakers, that are "passive",
with 3 Amplifiers driving them ALL.

Respect "Ohms Law!" and you can safely run in "series",

several speakers without presenting a low impedance that

is hard on the amplifier.

In addition, I implement 2 Velodyne subwoofers.

An 18" and a 15" one in front, one in the rear.

I implement front speakers, and side speakers, along

with rear center speakers.

Stereo ONLY, simply put, just 2 separate systems working

together to fill the room EVENLY with sound.

I have done speakers in both parallel and series, for over

30 years without ANY incidents at ALL.

PS Audio GCA 500, and a GCA-250 do the lions share,

while a Pro Hafler 300 wpc. @8ohms and 500wpc. @4ohms

for the side speakers.

NO sound processors are used, just PURE 2 channel sound

that is IMHO, the finest "Surround" Sound I have heard

so far.

Every speaker adds +3db. so you can see that this is an

easy way to squash the -10db. that most people have,

from their listening spot.

My idea was simple, 1 speaker must play very Loud to try

and fill a given room.

Placing speakers, in key locations where the hearing, is

able to pick up sound literally "ALL Around".

So I have plenty of "Headroom", and there is NO need to

ever increase the Volume, since the moment the "play"

button is engaged, it is as if a metamorphosis of the

Audio kind takes place.

Never be afraid to think outside the box.

Some of my Best ideas, have spawned out of the box.

Love Your Music!

Find a used David Hafler DH-200, DH-220 or DH-500. All can drive a two Ohm load with ease, utilizing MOS-FETs for output devices(not prone to thermal runaway). An operating 200 or 220 should be fairly inexpensive, and appear often on eBay. ie: (http://cgi.ebay.com/Hafler-Dh-200-Amplifier-Clean-Cheap-No-Reserve-1-Wow_W0QQitemZ390151415488QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item5ad6d626c0) You can find the manual for the DH-220 here: (http://www.hafler.com/techsupport/pdf/DH-220_amp_man.pdf)

Re connecting speakers in series:

1)To the extent that the speakers which are connected in series do not have identical impedance vs. frequency characteristics, frequency response irregularities will be introduced into each speaker. That is because the voltage applied by the amplifier across the series connected speaker string will divide up between the speakers differently at different frequencies, if the speaker impedances have different proportions to each other at different frequencies. Avoiding that effect will typically mean that the speakers should be identical models.

2)Even if the series connected speakers are identical models, bass damping will be degraded. That is because the source impedance driving each speaker will be the sum of the impedance of the other speaker and the power amp's output impedance, instead of just the power amp's output impedance.

Regards,
-- Al